Remote indicator and control device



June' 15, 1943. w. J. O'BRIEN 2,321,699

REMOTE INDICATOR AND CONTROL DEVICE Filed Oct. 1, 1940 2 Sheets-Sheet 1June 15, 1943- w. J. O'BRIEN REMOTE INDICATOR AND CONTROL DEVICE FiledOct. 1, 1940 2 Sheets-Sheet 2 Patented June 15, 1943 REMOTE INDICATORAND CONTROL DEVICE William J. OBrien, Chicago, Ill., assignor to EdwardF. Andrews, Chicago, Ill.

Application October 1, 1940, Serial N0. 359,270

6 Claims.

This invention relates to remote indicating and control devices andparticularly to indicators for such devices.

One of the objects of the invention to provide an improved indicator fora remote control unit comprising means for initiating a change ofcondition of a mechanism at remote position, and an indicator controlledby said last mechanism for indicating at the remote control posi tionresponse to said change of said mechanism.

A further object of the invention is to pro vide an improved remotecontrol for remotely Controlling devices through electrical connections.

A further object is to provide a remote indicator to indicate thefrequency to which th set is tuned at a remote point by means of astepping motor, the radio set being remotely controlledfrom a positionadjacent the indicator by means of a mechanism other than a steppingmotor, which is adapted to tune the set exactly to the frequency ofstations received.

A further object is to provide an improved indicator motor.

A further objcctis to provide a stator element of such a motor uponwhich the coils be wound cheaply and easily, resulting in an economicaland advantageous motor.

Other objects, advantages, and capabilitie of the invention will appearfrom the following description of preferred embodiments thereof, takenin conjunction with the accompanying drawings, in which 1 is adiagrammatic view of a remote con-- trol unit applied to the condenserof a radio set and an indicator located remotely with respect J to saidset for indicating the tuning condition of the condenser;

Fig. 1a is a diagrammatic view of a modified form of commutator;

' Fig. 1b is a diagrammatic view of a still further form of commutator;

Fig. 2 is a front view of an indicator unit embodying my invention;

Fig. 3 is a transverse sectional view taken therethrough, taken on theline 3-3 of Fig. 2:

Fig. 4 is a transverse section tl'ierethrough, taken on the line 4-4 ofFig. 3; and

Fig. 5 is a diagrammatic view illustrating the position of the coils andthe wiring of the indicating unit shown in Figs. 2, 3, and 4. v I

Referring to the drawinga -the reference numeral I6 designates thecondenser of a radio set, the remainder ofthe set being indicateddiagrammatically by the container I I. This particular radio set maycorrespond closely to the set described and claimed in the co-penomg aplication of Edward F. Andrews, Serial No. 275,- 437, filed May 24,1939.

The condenser I0 is adapted to be actuated in one direction or in theopposite direction by means of a reversible motor I2, which is connectedto the condenser I9 through gears I3, I4, :5, and IS, the gear 16 beingmounted on the shaft of the gang of condensers The operation of themotor I2 is started at the remote control unit, which is designatedgenerally by the reference numeral I8. Associated with this unit andpreferably in close propinquity thereto i an indicator generallyindicated by the reference numeral I9. As will readily be understoodfrom the aforesaid application, the remote control unit I8 comprises aswitch 20, whereby the volume of the set may be controlled, a switch 24for initiating the drive of the motor I2, and an adjustable arm 25 forcontrolling the sensitivity of the automatic means for stopping thecondenser I0 when a carrier of sufiicient strength is received.

The indicator l9 comprises a dial 26 provided with suitable indicia anda pointer 21. The pointer 21 is mounted on the shaft 28, which carriesthe rotor 29 of a motor, designated generally by the reference numeral30.

The rotor 29 is provided with a. series of teeth equally spaced aroundits periphery. The rotor 29 is of a magnetic metal and is preferablyconstituted of laminations.

The shaft 28 is rotatably mounted on suitable members carried by a framemember 34. The frame member 34 carries at suitable positions around therotor 29 three pole pieces 2|, 22, and 23. Each pole piece is providedwith a plurality of teeth directed towards and closely adjacent theteeth of the rotor 29. The teeth of each pole piece preferablycorrespond in size and spacing to the teeth of the rotor 29, thearrangement being such that all the teeth of each pole piece are adaptedto register with corresponding teeth of the rotor 29. The teeth of thepole pieces are preferably displaced in different relation to the teethof the rotor 29. Thus, the teeth of the pole piece 2 I, as shown in Fig.1, are in alignment with the adjacent teeth of the rotor 29, while theteeth of the pole pieces 22 and 23 are out of alignment with theadjacent teeth of the rotor 29.

It is preferred that the teeth of the pole pieces 22 and 23 shouldoverlap one-third of the adjacent teeth of the rotor 29 when the teethof the pole piece 2| are in alignment with the adjacent teeth of therotor 29. This overlap should occur on the sides of the teeth of thepole pieces 22 and 23 which are nearest to the pole piece 2|. That is,the left hand one-third of the teeth of the pole piece 22 should overlapthe adjacent teeth of the rotor 29 when the teeth of the pole piece 2|are in alignment with the adjacent teeth of the rotor 29. The polepieces 2|, 22, and 23 may suitably be of laminations of magneticmaterial. Each of the pole pieces 2|, 22, and 23 is provided with aWinding 3|, 32, and 33 respectively. It will thus be seen that when theWinding 32 is energized, the rotor 29 will move one step in theclockwise direction, as viewed in Fig. 1, whereas if the winding 33 isenergized, the rotor 29 will move one step in the counterclockwisedirection.

The gear |6 meshes with a pinion 35 carried by a shaft 36 which isrotatably mounted in a frame member 31. The shaft 36 has mountedthereon, with the aid of insulation, a commutator 38 which may suitablybe a disc of metal provided with a peripheral series of insulatinginsets 39. An insulated brush 40 bears against the commutator disc atall times. Three brushes 4|, 42, and 43 bear against the periphery ofthe commutator, these brushes being arranged to engage the commutator indiiferent phase relation. The brushes are biased towards the commutatorby means of suitable springs. The brushes 4|, 42, and 43, respectively,are connected by conductors 5|, 52, and 53, respectively, to thewindings 3|, 32, and 33, respectively. The other sides of these windingsare connected to a common conductor 44,-which is grounded at the set andis connected to one side of a battery 45 and to a condenser 46. Theother side of the battery and the other side of the condenser areconnected by a conductor 4'! to the brush 40. This conductor 41 may.include a choke coil 48 for a'purpose hereinafter to be described. Thereversible motor is provided with a common conductor 49 and twoconductors 50 and 54 which are connected together through a condenser55. The conductor 50 is connected to a contact 56, while the conductor54 is connected to a contact 51. Each of the contacts 56 and 51 isadapted to be engaged alternately by the contact arm 58, which isconnected to a conductor 59. An arm 60, rigidly connected to the switcharm 58, is adapted to be engaged by one or other of a pair of pins 6| or82, These pins may suitably be mounted on the gear I5 so as to move thearm 58 from one to the other of the contacts 56 and 51 when thecondenser attains its extreme position. Consequently, motor currentsupplied. from the set N passes through conductor 49 and either ofconductors 58 or 54 back to conductor 59 to drive themotor in onedirection or the other, depending upon the position of the arm 58.

For the purpose of preventing interference with the receiving set,caused by the commutator, the commutator, the motor 30, and the cable,which includes the conductors 44, 5|, 52, and 53, are surrounded by agrounded shield 64. The choke coil 48 and condenser 45 prevent any highfrequency disturbance from passing out of the shielded system to thebattery 45, or to any unshielded conductors from which it might betransferred'to the receiving set. It will be understood that the controlelements designated generally by the reference numeral l8 and theindicator 9 and motor 30 may be located in remote relation to thereceiving set I, the condenser l0, and the commutator 3B. Thus, forexample, the receiving set, including the condenser and associatedelement, may be located at the rear end of an the disc 38.

automobile, the control element l8 may be located on the steeringcolumn, convenient to the hand of the driver, and the control 25 and theindicator l9 and motor 30 may be located on the dashboard. Also, thecontrols 20, 24, and 25, together with the dial I9 and motor 30, may bemounted in a single compact container and connected to the radio set andcondenser H] by means of a single cable containing all the necessaryconductors.

The general control of the condenser ID will be fully understood fromthe disclosure of the aforesaid application and need not be describedhere in detail. It, sufilces to say that when the switch 24 is closedmomentarily, current is supplied through the circuit includingconductors 49 and iitlpand the motor is operated in one direction or theother until a station having sufficient carrier strength is received bythe set M. When that occurs, the motor I2 and condenser it areautomatically arrested to tune in the station providing that carrier.When the switch 24 is closed again, the condenser I0 is driven in thesame direction until another carrier is received and another stationtuned in. This continues until the condenser reaches the end of itstravel, whereupon the switch arm 58 is moved from one to the other ofthe contacts 56 and 51, and thereafter the condenser is moved fromstation to station in the opposite direction, tuning in the stations asbefore.

Assuming that the condensers are turning in the clockwise direction, asviewed in Fig. 1, the commutator 38 rotates in the opposite directionand the brushes 4|, 42, and 43 are successively connected to the battery45 in that order. Consequently, the poles 2|, 22, and 23 are energizedsuccessively in that order and the rotor 29 is rotated in the clockwisedirection in step with the movement of the condensers. When thecondensers are driven in the counterclockwise direction, the brushes areconnected to the battery in the order 4|, 43, and 42, and the polepieces are energized in the order 2|, 23, 22, so that the rotor 29 isrotated step by step in a counterclockwise direction in synchronism withthe movement of the condensers. The position of the condensers at anytime is indicated by the position of the pointer 25'! on the dial 26. Itis to be noted that the indicator is self-synchronizing. Thus, assumingthat the pointer 21 is out of synchronism with the condensers, being inadvance of the condensers when moving in one direction, then before thecondenser reaches its extreme position, the pointer 21 reaches itsextreme position in that direction and engages the adjacent pin or stop83. When the condensers reach their final position, the device issynchronized. Thus, all that is necessary to synchronize the indicatorwith the condensers is to drive the motor l2 to bring the condensersinto one extreme position and then into the other extreme position.

In the embodiment of the invention shown in 1, the insulating insets 39are of such length that at least one brush is always in engagement withthe conductive disc 38, and that for part of the time, another brush maybe in engagement with the conductive disc 38'. Thus, as shown in Fig. 1,only the brush 4| is in engagement with Assuming the condensers to berotated in the clockwise direction, the brush 42 engages the conductivesurface of the disc 38 so that both brushes 4| and 42 are connected tothe battery 45. Continued rotation of the condensers moves an insulatingsegment into engagement with brush 4|, leaving brush 42 alone connectedto the battery. The brush 43, which has been in engagement with aninsulating segment, now engages the conductive disc 38. Consequently,the pole piece 2| is energized, holding the adjacent teeth of the rotor29 in alignment with its teeth. Thereafter, both pole pieces 2| and 22become energized and the rotor makes a half step in the clockwisedirection. Thereafter the pole piece 2| becomes de-energized so that theteeth of the rotor move a half-step into alignment with the teeth of thepole piece 22. Thereafter the pole piece 23 becomes energized and theteeth make a further half-step in the clockwise direction. Then the polepiece 22 is de-energized and the rotor 29 makes a further half-step tobring its teeth into alignment with the teeth of the pole piece 23, andso on, the rotor 29 rotating in the clockwise direction by half-steps.

In the embodiment shown in Fig. 1A, the insulating insets 39 are ofsufficient length so that only one of the brushes 4|, 42, and 43 is inengagement with the disc 38 at a time. Consequently, the pole pieces 2|,22, and 23 are energized individually in that order or in the oppositeorder so that the rotor 25 moves one step on each energization of one ofthe poles. In the embodiment shown in Fig. 1B, the segments 39 are stilllonger, so that in the intermediate positions of the commutator 35%. nobrush is in engagement with the metallic surface of the disc 38. In thisembodiment of the invention, the poles 2 l, 22, and 23 are energizedsuccessively with intervals between successive energizations in which nopole is energized. preferred to employ friction means to preventmovement of the rotor 29 and associated elements when no pole isenergized. This friction means may suitably comprise a leaf spring 65which bears lightly against the rotor 29.

For high speed operation, it is preferred to reduce the mass of therotor as far as possible Without too great an increase in its reluctanceand to utilize the friction applied by the spring 65 to damp the rotor.For still higher speed operation, it is preferred to provide the rotorsystem with a frictionally mounted inertia member. This inertia membermay suitably consist of a flywheel 10 loosely mounted on the shaft 28.The flywheel is in frictional contact with the rotor 29, being biasedthereagainst by a coil spring 1| which abuts against a collar 12 mountedon the shaft 28. The flywheel ll] aids in preventing overstepping of therotor, dissipating excess energy when the rotor is arrested. One or theother of these expedients may be employed to stabilize the motor whenoperated from an alternating current source instead of from the battery45.

In Figs. 2, 3, 4, and 5 I show a modified form of indicator in whichsimilar parts are designated by the same reference numerals. Thisindicator is mounted within a housing 34 rovided with a window 66 forobservation of the pointer 27 and dial 26. The housing also carries aflange 61 whereby it may be mounted on an instrument board or in othersuitable locations.

In this modification, the spindle 28', preferably of magnetic material,is rotatably mounted in a hub member Ell which is rigidly mounted on theaxis of the housing 34. Thus a reduced end of the spindle 28' mayproject through a corresponding opening in the hub member 68. A

bronze bushing 69 provides a bearing at the outer end of the hub member68. The rotor 29 76 In this embodiment of the invention, it is isrigidly mounted on the spindle 28' adjacent the bushing 5|.

The hub member 68 is fixed to the pole system, the poles 2|, 22 and 23projecting radially outward from this hub member, their outer ends beingturned upwardly into the plane of the rotor 29. These upturned ends areprovided with teeth, two teeth in the embodiment shown, which arearranged to cooperate with the teeth of the rotor 29 in exactly the sameway as in the previously described embodiment.

The windings 3|, 32 and 33 are wound around the radial portions of thepoles 2|, 22 and 23, respectively, as diagrammatically shown in Fig. 5.These windings may therefore be built with great facility since thethree radial arm structure pro vides easy access for the winding of thecoil on each individual arm.

This embodiment of the invention differs from that shown in Fig. 1 inrelation to the magnetic circuit. Thus, in the previously describedembodiment, the magnetic circuit extended through the teeth from thepole piece on one side of each coil to the pole piece on the other sideof that coil. In this embodiment of the invention the magnetic circuitextends through each radial pole member, radially through the rotor 29,and back through the spindle 28 and hub member 68 back to the radialpole member.

The windings 3|, 32 and 33 are connected to conductors 5|, 52 and 53 andto a common conductor 3D. The shield may be employed as the commonconductor,

The operation of the indicator shown in Figs. 2 to 5 is preciselysimilar to that of the indicator previously described. It will beunderstood that the spring 65 and/or the frictional inertia flywheel 10may be applied to these embodiments, if desired.

It will be understood that the rotor 29 is preferably provided with alarge number of teeth to insure an accurate indication. The effectivenumber of teeth on the rotor, that is, the teeth which register with anytooth of a pole piece, should be equal to the number of conductiveportions of the commutator engaged by any brush during the travel of thedevice whose condition is being indicated from one of its extremepositions to the other. The commutator may be provided with any numberof conductive portions, depending upon the manner in which it isconnected to the device whose position is to be indicated. Thisconnection may be direct or through gearing, as shown in Fig. 1, It isalso preferable, for reasons of economy and accuracy, that the number ofteeth on the rotor should be very large relative to the three polesemployed on the stator. Thus, in Fig. 1, I have shown the rotor providedwith twenty-eight teeth. It will of course be understood that if moreaccurate indi cation is desired, the number. of teeth may be verygreatly increased. In this event, it will of course be understood thatthe commutator 38 is correspondingly changed to provide the increasednumber of impulses, from one end of the range of travel to the other,necessary to operate the indicator to its full extent.

Although the invention has been described in connection with specificdetails of preferred embodiments thereof, it must be understood thatsuch details are not intended to be limitative of the invention exceptinsofar as stated in the appended claims.

Having thus described my invention, what I claim and desire to secure byLetters the United States is:

1. In combination, a radio device having tuning means adapted to tunedesired stations to resonance and operable in opposite directionsbetween predetermined limits, a reversible motor for driving said tuningmeans in opposite direc tions, means including a motor controllingreversing switch operated in response to the position of aid tuningmeans for reversing the direction of movement of said tuning means atits limits of movement, a remote manual control for starting said motor,means operable in response to received signals for automaticallyarresting said motor when said tuning means is positioned to tune in astation, a tuning indicator located adjacent said remote control, amotor driving said tuning indicator, means operable in response to themovement of said tuning means for driving said last-mentioned motor inopposite directions in synchronism with said tuning means, and meansincluding means lim iting movement of said indicator at limitscorresponding to limits of movement of the tuning means forautomatically positionally synchronizing said indicator with said tuningmeans, in case it should be out of synchronism, upon movement of saidtuning means to both its limits, whereby automatic synchronization ofsaid indicator is insured when said tuning means is operated by itsdriving motor during the tuning in of stations.

2. A stepping motor for synchronous operation comprising a fieid framehaving three radial arms, the outer end of each arm being bent throu hsubstantially a right angle to form a pole piece, a winding on each arm,a magnetic rotor mounted in the center of said field frame, said rotorhaving a series of peripheral teeth in close proximity to said polepieces, said teeth being out of phase relative to said pole pieces byprogressive increments in both directions, and complementary bearingmeans on said frame and rotor providing a narrow air gap for the passageof magnetic flux induced by said windings between the center of thefield frame and the rotor.

23. A stepping motor for synchronous operation comprising a field framehaving three radial arms, the outer end of each arm being bent throughsubstantially a right angle to form a pole piece, a winding on each arm,magnetic rotor mounted in the center of said field frame, said rotorhaving a series of peripheral teeth in Patent of close proximity to saidpole pieces, said teeth being out of phase relative to said pole piecesby progressive increments in both directions, complementary bearingmeans on said frame and rotor providing a narrow air gap for the passageof magnetic flux induced by said windings between the center of thefield frame and the rotor, and means for limiting the movement of saidrotor.

4. A stepping motor comprising a field frame having at least threeradial arms, the outer end of each arm extending at substantially aright angle relative to the radial portion to form a pole piece, aWinding on each arm, a magnetic rotor mounted in the center of saidfield frame, said rotor having a series of peripheral teeth in closeproximity to said pole pieces, said teeth being out of phase relative tosaid pole pieces by progressive increments in both directions, andcomplementary bearing means on said frame and rotor providing a narrowair gap for the passage of magnetic flux induced by said Windingsbetween the center of the field frame and the rotor.

5. A stepping motor'comprising a field frame having at least threeradial arms, the outer end of each arm extending at an angle relative tothe radial portion to form a pole piece, a winding on each arm, amagnetic rotor mounted in the center of said field frame, said rotorhaving a series of peripheral teeth in close proximity to said polepieces, said teeth being out of phase relative to said pole pieces byprogressive increments in. both directions, and complementary bearingmeans on said frame and rotor providing a narrow air gap for the passageof magnetic flux induced by said windings between the center of thefield frame and the rotor.

6. A stepping motor comprising a field frame having at least threeradial arms, the outer ends of which form pole pieces, a winding on eacharm, a magnetic rotor having a series of peripheral teeth, the rotorteeth and the outer ends of the radial arms being angularly disposed inenveloping relation to'each other and in close proximity to each otherand the rotor teeth being out of phase relative to said pole pieces byprogressive increments in both directions, and complementary bearingmeans on said frame and rotor providing a narrow air gap for the passageof magnetic flux induced by said windings between the center of thefield frame and the rotor.

WILLIAM J. QBRIEN.

